Mercaptoketones and mercaptoalcohols and a process for their preparation

ABSTRACT

This invention relates to matrix metalloproteinase (MMP) inhibiting compounds of the formula: ##STR1## where R 1  is C 1  -C 12  alkyl, straight or branched and optionally substituted by halogen, hydroxy, C 1  -C 6  alkoxy, amino, carboxyl, C 1  -C 6  alkoxycarbonyl, carboxamido, nitrile, mono- or di-(C 1  -C 6 )alkylamino, thio, C 1  -C 6  alkylthio, aryl, --Oaryl or --OCH 2  aryl where aryl is optionally substituted with C 1  -C 6  alkyl, C 1  -C 6  alkoxy, carboxy, halogen, cyano, nitro, carboxamido, or hydroxy; and C 1  -C 6  alkanesulfonyloxy. R 2  is α-OH or β-OH and R 6  is H or R 2  and R 6  together are carbonyl; the chemical intermediates; and processes for the preparation of these compounds and the intermediates thereto. 
     Matrix metalloproteinases (MMP) are a family of zinc-containing calcium dependent proteinases, including stromelysins, collagenases, and gelatinases. These MMP enzymes are capable of degrading the proteinaceous components of connective tissue and appear to be involved in tissue remodeling, i.e., wound healing and connective tissue turnover. Unexpectedly, the mercaptoalcohols with the S-configuration at the hydroxyl-bearing carbon have been found to be at least 4 times more potent than the analogous (R)-alcohols both in vitro and in vivo in inhibiting the MMP enzyme.

This application is a divisional of application Ser. No. 08/887,000,filed Jul. 2, 1997, now U.S. Pat. No. 5,852,213, which is a continuationof provisional application Ser. No. 60/022,469, filed on Jul. 10, 1996.

FIELD OF INVENTION

This invention relates to mercaptoketone and diastereomericmercaptoalcohol derivatives of Formula I useful as matrixmetalloproteinase inhibitors and a process for the stereospecificsynthesis of each of the diasteromers. Unexpectedly, themercaptoalcohols with the S-configuration at the hydroxyl-bearing carbonhave been found to be at least 4 times more potent than the analogous(R)-alcohols both in vitro and in vivo.

BACKGROUND OF THE INVENTION

Matrix metalloproteinases (MMP) are a family of zinc-containing calciumdependent proteinases, including stromelysins, collagenases, andgelatinases. These MMP enzymes are capable of degrading theproteinaceous components of connective tissue and appear to be involvedin tissue remodeling, i.e., wound healing and connective tissueturnover. Approximately thirteen MMPs have been identified. Thecollagenases cleave fibrillar collagen. The stromelysins degradefibronectin, laminin, and proteoglycans in addition to collagen. Thegelatinases can degrade denatured collagen (gelatin) and type IVcollagen, the major component of basement membranes.

Elevated levels of collagenase and stromelysin are associated with bothosteo- and rheumatoid arthritis, having been observed both in synoviumand cartilage in amounts proportional to the severity of the disease.The gelatinases are thought to play a key role in tumor metastasis,since they degrade the basement membrane through which tumor cells mustpass in order to migrate away from the primary tumor site and thusenable the migration from the primary site. Gelatinase is alsoassociated with the process of angiogenesis which is essential for thegrowth of solid tumors. In addition to the association with osteo- andrheumatoid arthritis and tumor metastasis, MMPs are implicated incorneal ulceration, gingivitis, multiple sclerosis and otherneurological disorders, and emphysema (Beeley et al., Curr. Opin. Ther.Patents 4(1), 7-16 (1994)).

Compounds which bind zinc at the active site of the enzyme prevent thecatalytic activity of MMPs. MMP inhibitor activity has been found incertain peptidyl hydroxamic acids, peptidylalkyl carboxylic acids,peptidylphosphinic and phosphonic acids. Furthermore, peptidyl thiolsincorporating a carbonyl group two atoms removed from the thiol grouphave been shown to be potent MMP inhibitors. For example, in thecompound below, as disclosed in Journal of Medicinal Chemistry 36,4030-4039 (1993), the SSR ##STR2## isomer is a potent (IC₅₀ =2 nM)inhibitor of human collagenase (J. R. Morphy et al., Current MedicinalChemistry 2,743-762 (1995).

Merck discloses the compound ##STR3## in the PCT application WO 9407481as a moderate inhibitor of the MMP stromelysin. The compound ##STR4## isdisclosed in the PCT application WO 9513289. The mercapto sulfide MMPinhibitor compound below was disclosed in the PCT application WO9509833. ##STR5## MMP inhibiting compounds of the formula ##STR6## whereP is H, methyl or phenyl are disclosed by Donald et al., U.S. Pat. No.4,595,700. The compound where P is 2-oxopropyl is approximately 20 timesmore potent than the compound where P is methyl which is in turn about20 times more potent than the compound where P is hydrogen (EP 0322,184A2). In all of the above noted examples the thiol moiety is two carbonsremoved from an amides carbonyl group.

BRIEF DESCRIPTION OF THE INVENTION

The matrix metalloproteinase inhibiting compounds of this invention arerepresented by formula I ##STR7## where R¹ is C₁ -C₁₂ alkyl, straight orbranched and optionally substituted by halogen, hydroxy, C₁ -C₆ alkoxy,amino, carboxyl, C₁ -C₆ alkoxycarbonyl, carboxamido, nitrile, mono- ordi-(C₁ -C₆)alkylamino, thio, C₁ -C₆ alkylthio, aryl, --Oaryl or --OCH₂aryl where aryl is optionally substituted with C₁ -C₆ alkyl, C₁ -C₆alkoxy, carboxy, halogen, cyano, nitro, carboxamido, or hydroxy; and C₁-C₆ alkanesulfonyloxy. R² is α-OH or β-OH and R⁶ is H or R² and R⁶together forms carbonyl. In the above definition, aryl is a 5 to 10membered carbocyclic or heterocyclic mono or bicyclic aromatic groupsuch as benzene, furan, thiophene, imidazole, naphthalene, quinoline,indole, benzothiophene, benzimidazole, pyridine, pyrimidine orbenzofuran. This invention also encompasses all of the chemicalintermediates required for the synthesis of compounds of formula I.

The diastereomeric compounds of formula I have been shown to inhibit thematrix metalloproteinases collagenase, stromelysin and gelatinase, bothin vitro and in vivo. and are thus expected to be useful in thetreatment of arthritis, corneal ulceration, multiple sclerosis,gingivitis, emphysema, inhibition of solid tumor growth, and preventionof tumor metastasis. The stereospecific synthesis of themercaptoalcohols is desirable since the alcohols of the(S)-configuration (formula I, R² is β-OH) have been found to be at least4 times more potent than the corresponding (R)-configured diastereomersboth in vitro and in vivo. Disclosed herein is a process by which eitherof the two diastereomers of compounds of formula I (R² is α-OH or β-OH)can be synthesized via intermediate lactone diastereomers. Alsodisclosed herein are diastereomerically and entaniomerically pureintermediates and processes for their preparation.

DETAILED DESCRIPTION OF THE INVENTION

The process for the sterospecific synthesis of each of thediastereomeric alcohols and ketones of Formula I is shown in Schemes I,II, and III. Schemes II and III outline alternate synthesis ofdiastereomeric furanone intermediates. The Roman numerals following thenames of the compounds refer to structures shown in Schemes I, II, andIII. Those skilled in the art of organic synthesis will recognize thatstereochemical directing groups other than(S)-(-)-4-benzyl-2-oxazolidinone (A) as shown in Scheme I, including,but not limited to, alternatively substituted oxazolidinones, ephedrinederivatives and chiral 2,10-camphorsultams may be used to obtain thesame results. Also, hydroxyl and mercaptan protecting groups other thanthose used herein in the following specific examples can be utilized.Thiol protecting groups, W, which can be used include phenyl, --C(O)arylwhere aryl is as defined and optionally substituted as above, --C(O)C₁-C₁₂ alkyl, --CR³ R⁴ R⁵ where R³, R⁴ and R⁵ are independently H, methyl,--OC₁ -C₁₂ alkyl, O-tetrahydropyranyl, --S-benzyl, and phenyl optionallysubstituted by methoxy, hydroxy, nitro, or methyl; disulfides or anyother group suitable for protecting sulfur. Thiol protecting groups Zare H, phenyl, --CR³ R⁴ R⁵ where R³, R⁴ and R⁵ are independently H,methyl, --OC₁ -C₁₂ alkyl, O-tetrahydropyranyl, --S-benzyl, and phenyloptionally substituted by methoxy, hydroxy, nitro, or methyl; disulfidesor any other group suitable for protecting sulfur. Hydroxyl protectinggroups Y, include trimethylsilyl, t-butyldimethylsilyl, triethylsilyl,i-propyldimethylsilyl, trityldimethylsilyl, t-butyldiphenylsilyl,methyldi-i-propylsilyl, methyldi-t-butylsilyl, tri-i-propylsilyl,triphenylsilyl, benzyl, benzyl optionally substituted with methoxy,nitro, halo, cyano; and substituted methyl and ethyl ethers includingtriphenylmethyl, methoxymethyl, methoxyethoxymethyl, tetrahydropyran andallyl. Still other suitable oxygen and sulfur protecting groups asdescribed in "Protective Groups in Organic Synthesis" (2nd ed., T. W.Greene and P. G. M. Wuts, John Wiley & Sons, New York, N.Y., 1991) maybe used. Additionally, it will be apparent to those skilled in the artof organic synthesis that removal of the various chiral auxiliaries andmercapto and hydroxyl protecting groups may require methods other thanthose used in Schemes I, II, and III. It is understood by those skilledin the art that the various functionalities present on the molecule mustbe consistent with the chemical transformations proposed. This willfrequently necessitate judgment as to the order of synthetic steps,protecting groups and deprotecting conditions.

Invention compounds and intermediates where R¹ is optionally substitutedcan be prepared following the steps outlined in schemes I, II, and IIIand following the procedures given in the examples starting with anappropriately substituted carboxylic acid of the formula R¹ CH₂ COOH oracid halide or anhydride thereof. Such acids are either commerciallyavailable or can be prepared according to standard literatureprocedures. Obviously, depending on the functionality of thesubstituent, standard protecting group chemistry may be required.

The formula I compounds of this invention where R² is α-OH (Rconfiguration) or β-OH (S configuration) are prepared individuallyaccording to the process disclosed herein as outlined in Scheme I,starting with a common chiral acid 2(R)-2-R¹ -pent-4-enoic acid offormula i. These 2-substituted pent-4-enoic acids are prepared accordingto literature procedures or by the sequence of reactions shown in SchemeI and in the following examples 1-6.

A synthetic scheme for preparing the starting acids (i) is shown inScheme I. (4S)-4-Benzyl-3-((2R)-2-R¹ -pent-4-enoyl)oxazolidin-2-ones, B,are prepared by acylation of (S)-(-)-4-benzyl-2-oxazolidinone, A, withan alkanoic acid halide of the formula R¹ CH₂ C(O)-halogen or the acidanhydride thereof, where R¹ is C₁ -C₁₂ alkyl as defined above. A varietyof N-acyl oxazolidinones, A, are known in the literature, includingalkyl-O-CH₂ aryl and alkyl-aryl derivatives which have previously beenused for the synthesis of MMP inhibitors (Tomczuk, B. E. et. al. Bioorg.& Med. Chem. Lett. 5, 343, 1995; Chapman, K. T., et. al. Bioorg. & Med.Chem. Lett. 6, 803, 1996). The acyl chain is then alkylatedstereospecifically ax to the carbonyl with an allylating agent such asallyl halide or triflate, preferably allyl bromide, and the resulting(4S)-4-benzyl-3-((2R)-2-R^(1-pent-) 4-enoyl)oxazolidin-2-one ishydrolyzed with lithium hydroperoxide or other suitable aqueous base togive the (2R)-2-R¹ -penten-4-oic acids (i).

Reaction of the acid (i)with iodine affords predominantly thedihydrofuranone of formula iib, whereas reaction of the dimethylamide ofthe acid i with iodine affords predominantly the dihydrofuranone offormula iia. Either of the iodomethyldihydrofuranones iia or iib isconverted to a protected thiol (iiia or iiib) by reaction with the anionof HSW, when appropriate, where W is as defined above, preferably by thesodium, lithium or potassium salt of thiolacetic acid. S-acetylthiomethyldihydrofuranone iiia or iiib (W=Ac) is then hydrolyzed and thethiol protected as a cleavable thiol ether --SZ to give iva or ivb,where Z is defined as H, phenyl, --CR³ R⁴ R⁵ where R³, R⁴ and R⁵ areindependently H, methyl, --OC₁ -C₁₂ alkyl, O-tetrahydropyranyl,--S-benzyl, and phenyl optionally substituted by methoxy, hydroxy,nitro, or methyl; disulfides or any other group suitable for protectingsulfur. The preferred protecting group Z for iva and ivb is thetriphenylmethyl group which is readily formed from the thiol and tritylchloride in trifluoroacteic acid and is resistant to chemical reactionsthat occur in subsequent process steps.

Hydrolysis of the dihydrofuranone iva or ivb produces the S-protected4-hydroxy-5-mercaptopentanoic acid va or vb respectively. The hydroxygroup of the pentanoic acid va or vb is protected by a group Y byformation of an ether where Y is defined as H, trimethylsilyl,t-butyldimethylsilyl, triethylsilyl, i-propyldimethylsilyl,trityldimethylsilyl, t-butyldiphenylsilyl, methyldi-i-propylsilyl,methyldi-t-butylsilyl, tri-i-propylsilyl, triphenylsilyl, benzyl, benzyloptionally substituted with methoxy, nitro, halogen or cyano,triphenylmethyl, methoxymethyl, methoxyethoxymethyl, tetrahydropyran andallyl. The preferred protecting group Y is the t-butyldimethylsilylgroup.

A O,S-protected acid via or vib is coupled with2(S)-t-butyl-N-methylglycine using standard amide coupling techniques toobtain the respective protected formula I compound viia or viib. Removalof the hydroxyl protecting group (Y) gives the S-protected formula Icompound viiia or viiib respectively. Removal of the sulfur protectinggroup (Z) from viiia or viiib then gives a formula I compound where R²is β-OH (S configuration) or α-OH (R configuration) respectively. Eitherof the formula I compounds where R² is OH and R⁶ is H and Z is aprotecting group can be oxidized followed by removal of the protectinggroup to give a compound of formula I where R² and R⁶ together form acarbonyl group.

Thioacetic acid ester iiia or iiib (W=Ac) is also available via thecommercially available (R)-(-)- or(S)-(+)-dihydro-5-(hydroxymethyl)-2(3H)-furanone as shown in Scheme II.Thus, protection of the hydroxy group of the (S)-(+) enantiomer as thet-butyldimethylsilyl ether or any suitable bulky protecting group suchas a trityl group, followed by deprotonation of the resulting lactoneand alkylation of this anion with R¹ X, where R¹ is as previouslydefined and X is a suitable leaving group such as halide or triflate,gives lactone x. Lactone x is also available via alkylation of asuitably substituted pseudoephedrine amide, or via the alkylation of anachiral amide enolate with an enantiomerically pure epoxide followed byacid-induced hydrolysis/equilibration (Myers, A. G., et. al. J. Org.Chem. 61, 2428, 1996). Subsequent deprotection of the alcohol provides2(R)-2-R¹ -5(S)-5-hydroxymethyldihydrofuran-2-one(xia). (Lewis, C. N.et. al. JCS Chem. Commun. 1786, 1987). This alcohol may be convertedinto lactone-thioacetate iiia via a Mitsunobu-type reaction (Volante, R.P. Tetrahedron Letters, 22, 3119, 1981) or by conversion of the alcoholinto a suitable leaving group such as halide, triflate, mesylate ortosylate followed by displacement with thiolacetic acid or othersuitable protected thiol equivalent and base. Using the same methodology(R)-(-)-dihydro-5-(hydroxymethyl)-2(3H)-furanone can be converted intothioacetate-lactone iiib via hydroxy-lactone intermediate xib (SchemeII).

Also, both diastereomeric lactones iiia and iiib can be synthesized fromthe pentenoic acid i as shown in Scheme III. Asymmetric dihydroxylationof the acid using Sharpless methodology (Sharpless, K. B., et. al. Chem.Rev. 94, 2483, 1994) provides diol xii which then undergoes acidcatalyzed lactonization to give either of lactone-alcohols xia or xib.The lactones are then converted into the correspondingthioacetate-lactones, iiia or iiib via the same methodology describedabove for the conversion of iia to iiia in Scheme II. ##STR8##

The following examples illustrate the process described above and areincluded for illustrative purposes only and are not to be construed aslimiting to this invention in any way. The chemicals and reagents usedin these procedures are either commercially available or readilyprepared according to literature procedures by those skilled in the artof synthetic organic chemistry.

EXAMPLE 1 (S)-3-(1-Oxononanyl)-4-(phenylmethyl)-2-oxazolidinone

To a solution of 15.80 g (0.10 mol) of nonanoic acid in 150 mL ofdichloromethane at 0° C. was added 0.1 mL of N,N-dimethylformamide and9.59 mL (0.11 mol) of oxalyl chloride. The reaction mixture was allowedto warm to room temperature and stirred overnight. The reaction mixturewas then concentrated in vacuo, diluted with hexanes and filtered. Thefiltrate was concentrated in vacuo to provide 17.67 g (100%) of nonanoylchloride which was used without further purification in the next step.

To a solution of 25.2 g (0.142 mol) of (S)-(-)-4-benzyl-2-oxazolidinone(Aldrich Chemical Company) in 300 mL of THF cooled to -78° C. was added97.0 mL (0.155 mol) of 1.6M n-butyllithium. The reaction mixture wasstirred at -78° C. for 1 hour and nonanoyl chloride (17.4 g, 0.129 mol),dissolved in 75 mL of THF, was then added. The resulting mixture wasstirred at -78° C. for 3 hours and then quenched with 5% HCl solution.The resulting mixture was extracted with ether and the combined organicswere washed with water, saturated sodium bicarbonate and brine. Theorganics were then dried over MgSO₄, filtered and concentrated in vacuo.The residue was chromatographed on silica gel, eluting with ethylacetate/hexanes (1:10), to provide 24.75 g (78%) of the desired productas a white solid.

EXAMPLE 2 (S)-3-(4-Metliyl-1-oxopentyl)-4-(phenylmethyl)-2-oxazolidinone

Following the above procedure and substituting 15.0 g (0.129 mol) of4-methylvaleric acid for the nonanoic acid, 23.69 g (66%) of the titlecompound is obtained.

EXAMPLE 3 (4S)-4-Benzyl-3-((2R)-2-heptyl-pent-4-enoyl)oxazolidin-2-one

To a solution of 5.50 g (0.017 mol) of the oxazolidinone in 40 mL ofTHF, cooled to -78° C., was added 17.3 mL (0.035 mol) of a 2.0M solutionof lithium diisopropylamide in heptane/THF/benzene. The resultingmixture was stirred at -78° C. for 1 h and then neat allyl bromide (7.5mL, 0.087 mol) was added to the reaction mixture. The reaction wasallowed to warm to 0 degrees (ice bath) and stirred for an additional 3h and then quenched with 5% HCl solution. The resulting mixture wasextracted with ether and the combined organic layers were washed withwater and brine, dried over MgSO₄, filtered and concentrated in vacuo.The residue was chromatographed on silica gel eluting with ethylacetate/hexanes (1:10) to provide 5.0 g (81%) of the desired alkylatedproduct as a colorless oil. Electrospray Mass Spec: 358.2 (M+H)⁺.

EXAMPLE 4 (4S)-4-Benzyl-3-((2R)-2-isobutyl-pent-4-enoyl)oxazolidin-2-one

In the same manner as described in Example 3 allylation of the isobutylsubstituted oxazolidinone proceeded in 85% yield to provide the productas a colorless oil. CI Mass Spec: 316.3 (M+H).

EXAMPLE 5 (2R)-2-Heptyl-pent-4-enoic acid

To a solution of 8.69 g (0.024 mol) of the product from Example 3 in 425mL of THF/H₂ O (3:1), cooled to 0 degrees, was added 10.8 mL (0.097 mol)of 30% hydrogen peroxide solution followed by 2.03 g (0.049 mol) ofLiOH--H₂ O. The resulting solution was stirred at 0° C. for 1.5 h andthen quenched with a solution of 15.4 g of sodium sulfite in 100 mL ofH₂ O. The reaction mixture was then acidified to pH 3 with aqueous HCland extracted with EtOAc. The combined organic layers were washed withwater and brine, dried over MgSO₄, filtered and concentrated in vacuo.The residue was chromatographed on silica gel eluting with ethylacetate/hexanes (1:10) to provide 4.33 g (90%) of the desired product asa colorless oil. CI Mass Spec: 199 (M+H).

EXAMPLE 6 (R)-2-Isobutyl-pent-4-enoic acid

In the same manner as described in Example 5 hydrolysis of the productof Example 4 proceeded in 92% yield to provide the product as acolorless oil. CI Mass Spec: 157.2 (M+H).

EXAMPLE 7 (R)-2-Heptyl-pent-4-enoic acid dimethylamide

To a mixture of 5.00 g (0.025 mol) of the product of Example 5 and 2.27g (0.028 mol) of dimethylamine hydrochloride in DMF at 0° C. was added4.21 mL (0.028 mol) of diethyl cyanophosphonate followed by 7.38 mL(0.053 mol) of triethylamine. The reaction mixture was stirred at 0degrees for 1 h and then at room temperature for 3 h. The resulting paleyellow suspension was diluted with 750 mL of EtOAc/Hex (2:1) and thissolution was then washed with 5% aqueous HCl solution, water, saturatedsodium bicarbonate and brine. The organic layer was dried over magnesiumsulfate, filtered and concentrated in vacuo. The residue waschromatographed on silica gel eluting with ethyl acetate/hexanes (1:4)to provide 5.68 g (100%) of the title compound as a colorless oil. CIMass Spec: 226.3 (M+H).

EXAMPLE 8 (R)-2-Isobutyl-pent-4-enoic acid dimethylamide

In the same manner as described in Example 7 the product of Example 6gave an 88% yield of the corresponding N,N-dimethyl amide as a colorlessoil. CI Mass Spec: 184.2 (M+H).

EXAMPLE 9 (3R,5S)-3-Heptyl-5-iodomethyl-dihydrofuran-2-one

To a mixture of 5.68 g (0.025 mol) of the product of Example 7 in 90 mLof DME/H₂ O (1:1) at room temperature was added 7.69 g (0.030 mol) ofiodine. The resulting solution was stirred at room temperature for 60 hand then diluted with ether and washed successively with a saturatedaqueous solution of Na₂ S₂ O₃, saturated sodium bicarbonate solution andbrine. The organic layer was dried over magnesium sulfate, filtered andconcentrated in vacuo. The residue was chromatographed on silica geleluting with ethyl acetate/hexanes (1:10) to provide 5.11 g (63%) of thetitle compound as a white solid and 0.788 g (10%) of the iodo-cislactone as a colorless oil. CI Mass Spec: 325.3 (M+H).

EXAMPLE 10 (3R,5S)-5-Iodomethyl-3-isobutyl-dihydrofuran-2-one

In the same manner as described in Example 9 4.14 g (0.023 mol) of theproduct of Example 8 gave 4.539 g (71%) of the title compound as acolorless oil along with 0.691 g (11%) of the corresponding iodo-cislactone. CI Mass Spec: 283.2 (M+H).

EXAMPLE 11 (3R,5R)-3-Heptyl-5-iodomethyl-dihydrofuran-2-one

To a solution of 7.14 g (0.036 mol) of the product of Example 5 in 750mL of THF/H₂ O (2:1), cooled to 0 degrees, was added 7.22 g (0.072 mol)of KHCO₃ followed by 11.97 g (0.072 mol) of KI and then 18.30 g (0.072mol) of iodine. The reaction was allowed to warm to room temperature andstirred for 18 h. The resulting mixture was diluted with ether and theorganic layer was washed with aqueous sodium bisulfite solution, H₂ Oand brine, dried over MgSO₄, filtered and concentrated in vacuo. Theresidue was chromatographed on silica gel eluting with ethylacetate/hexanes (1:10) to provide 8.30 g (71%) of the title compound and3.36 g (29%) of the corresponding iodo-trans lactone as white solids. CIMass Spec: 325.3 (M+H).

EXAMPLE 12 (3R,5R)-5-Iodomethyl-3-isobutyl-dihydrofuran-2-one

In the same manner as described in Example 11 iodolactonization of 6.29g (0.04 mol) of the product of Example 4 proceeded to provide 7.21 g(63%) of the title compound and 3.77 g (33%) of the correspondingiodo-trans lactone as colorless oils. CI Mass Spec: 283.2 (M+H).

EXAMPLE 13 Thioacetic acidS-((2R,4R)-4-heptyl-5-oxo-tetrahydrofuran-2-ylmethyl)ester

To a solution of 6.49 g (0.020 mol) of the product of Example 11 in 50mL of dry methanol was added 1.19 g (0.022 mol) of sodium methoxidefollowed by 5.73 mL (0.080 mol) of thiolacetic acid. The resultingmixture was heated at reflux for 4.5 h and then cooled to roomtemperature and acidified with 5% HCl solution. The resulting solutionwas extracted with ether and the combined organic layers were washedwith water and brine, dried over MgSO₄, filtered and concentrated invacuo. The residue was chromatographed on silica gel eluting with ethylacetate/hexanes (1:10) to provide 5.08 g (93%) of colorless oil. CI MassSpec: 273.3 (M+H).

EXAMPLE 14 Thioacetic acidS-((2S,4R)-4-heptyl-5-oxo-tetrahydrofuran-2-ylmethyl)ester

In the same manner as described in Example 13 the product of Example 9was converted into the corresponding thioacetate, obtained as acolorless oil in 82% yield. CI Mass Spec: 273.3 (M+H).

EXAMPLE 15 Thioacetic acidS-((4S,2R)-4-isobutyl-5-oxo-tetrahydrofuran-2-ylmethyl)ester

In the same manner as described in Example 13 the product of Example 12was converted into the corresponding thioacetate, obtained as acolorless oil in 75% yield. CI Mass Spec: 231.3 (M+H).

EXAMPLE 16 Thioacetic acidS-((2S,4R)-4-isobutyl-5-oxo-tetrahydrofuran-2-ylmethyl)ester

In the same manner as described in Example 13 the product of Example 10was converted into the corresponding thioacetate, obtained as acolorless oil in 75% yield. CI Mass Spec: 231.3 (M+H).

EXAMPLE 17 (3R,5R)-3-Heptyl-5-tritylsulfanylmethyl-dihydrofuran-2-one

To a solution of the product of Example 13 in 100 mL of methanol, cooledto 0° C., was added 2.69 g (0.071 mol) of solid sodium borohydride inportions over 15 minutes. The reaction was then concentrated in vacuo,acidified with 10% HCl solution and extracted with methylene chloride.The combined organic layers were washed with water and brine, dried overMgSO₄, filtered and concentrated in vacuo. The resulting crude thiol wasdissolved in 50 mL of trifluoroacetic acid and 5.98 g (0.023 mol) oftrityl alcohol was added. After stirring at room temperature for 1 h thereaction mixture was concentrated in vacuo and the residue waschromatographed on silica gel eluting with ethyl acetate/hexanes (1:50)to provide 5.26 g (61%) of the desired product as a colorless oil. CIMass Spec: 473.5 (M+H).

EXAMPLE 18 (3R,5S)-3-Heptyl-5-tritylsulfanylmethyl-dihydrofuran-2-one

In the same manner as described in Example 17 the product of Example 14was converted into the corresponding S-trityl derivative, obtained as acolorless oil in 65% yield. CI Mass Spec: 473.5 (M+H).

EXAMPLE 19 (3R,5R)-3-Isobutyl-5-tritylsulfanylmethyl-dihydrofuran-2-one

In the same manner as described in Example 17 the product of Example 15was converted into the corresponding S-trityl derivative, obtained as acolorless oil in 64% yield. CI Mass Spec: 431.4 (M+H).

EXAMPLE 20 (3R,5S)-3-Isobutyl-5-tritylsulfanylmethyl-dihydrofuran-2-one

In the same manner as described in Example 15 the product of Example 14was converted into the corresponding S-trityl derivative, obtained as acolorless oil in 61% yield. CI Mass Spec: 431.5 (M+H).

EXAMPLE 21 (2R)-2-((2R)-2-Hydroxy-3-tritylsulfanylpropyl)nonanoic acid

To a solution of 3.72 g (7.88 mmol) of the product of Example 17 in 10mL of methanol/THF (1:1) at room temperature was added 16.7 mL of 1.0NNaOH solution. The reaction was stirred at room temperature for 1 h andthen diluted with 100 mL of H₂ O and carefully acidified to pH 6 with 5%HCl solution. The resulting mixture was extracted with EtOAc and thecombined organic layers were washed with water and brine, dried overMgSO₄, filtered and concentrated in vacuo. The residue, 3.72 g (100%) ofthe crude hydroxy-acid was used in the next step (Example 25) withoutfurther purification. Electrospray Mass Spec: 489.4 (M-H)⁻.

EXAMPLE 22 (2R)-2-((2S)-2-Hydroxy-3-tritylsulfanylpropyl)nonanoic acid

In the same manner as described in Example 19 the product of Example 16was converted into the corresponding hydroxy-acid derivative, obtainedas a colorless oil in 95% yield. Electrospray Mass Spec: 489.4 (M-H)⁻.

EXAMPLE 23 (2R,4R)-4-Hydroxy-2-isobutyl-5-tritylsulfanylpentanoic acid

In the same manner as described in Example 21 the product of Example 19was converted into the corresponding hydroxy-acid derivative, obtainedas a colorless oil in 99% yield. Electrospray Mass Spec: 447.3 (M-H)⁻.

EXAMPLE 24 (2R,4S)-4-Hydroxy-2-isobutyl-5-tritylsulfanylpentanoic acid

In the same manner as described in Example 21 the product of Example 20was converted into the corresponding hydroxy-acid derivative, obtainedas a colorless oil in 99% yield. Electrospray Mass Spec: 447.3 (M-H)⁻.

EXAMPLE 25(2R)-2-[(2R)-2-(tert-Butyl-dimethylsilanyloxy)-3-tritylsulfanylpropyl]nonanoicacid

To a solution of 3.72 g (7.88 mmol) of the crude product of Example 21dissolved in 10 mL of DMF was added 2.68 g (0.039 mol) of imidazolefollowed by 2.85 g (0.019 mol) of t-butyldimethylsilyl chloride. Thereaction mixture was stirred at room temperature for 2 h and then pouredinto 200 mL of H₂ O. The resultIng solution was extracted with ether andthe combined organic layers were washed with water and brine, dried overMgSO₄, filtered and concentrated in vacuo. The residue was dissolved in10 mL of methanol/THF (1:1) and 5.0 mL of 1N NaOH solution was added.After stirring for 0.75 h at room temperature the reaction mixture wasacidified with 5% HCl solution to pH 5 and then extracted with ether.The combined organic layers were washed with water and brine, dried overMgSO₄, filtered and concentrated in vacuo. The residue waschromatographed on silica gel eluting with ethyl acetate/hexanes (1:10)to provide 4.76 g (100%) of the desired product as a colorless oil.Electrospray Mass Spec: 603.5 (M-H)⁻.

EXAMPLE 26(2R)-2-[(2S)-2-(tert-Butyl-dimethylsilanyloxy)-3-tritylsulfanylpropyl]nonanoicacid

In the same manner as described in Example 25 the product of Example 22was converted into the corresponding TBDMS ether-acid derivative,obtained as a colorless oil in 83% yield. Electrospray Mass Spec: 603.5(M-H)⁻.

EXAMPLE 27(2R,4S)-4-(tert-Butyldimethylsilanyloxy)-2-isobutyl-5-tritylsulfanylpentanoicacid

In the same manner as described in Example 25 the product of Example 24was converted into the corresponding TBDMS ether-acid derivative,obtained as a colorless oil in 91% yield. Electrospray Mass Spec: 561.4(M-H)⁻.

EXAMPLE 28(2R,4R)-4-(tert-Butyldimethylsilanyloxy)-2-isobutyl-5-tritylsulfanylpentanoicacid

In the same manner as described in Example 25 the product of Example 23was converted into the corresponding TBDMS ether-acid derivative,obtained as a colorless oil in 95% yield. Electrospray Mass Spec: 561.4(M-H)⁻.

EXAMPLE 29(2R)-2-[(2R)-2-(tert-Butyl-dimethylsilanyloxy)-3-tritylsulfanylpropyl]-nonanoicacid ((1S)-2,2-dimethyl-1-methylcarbonylpropyl)amide

To a solution of 4.76 g (7.88 mmol) of the product of Example 25dissolved in 150 mL of dichloromethane was added 1.42 g (9.85 mmol) oft-butyl glycine-N-methylamide followed by 1.86 mL (0.013 mmol) oftriethylamine and 1.67 mL (0.011 mmol) of diethylcyanophosphonate. Thereaction mixture was stirred at room temperature for 12 h and thenconcentrated in vacuo. The resulting residue was diluted with ether andthe organics were washed with 5% HCl solution, water and brine. Theorganic layer was then dried over MgSO₄, filtered and concentrated invacuo to provide 5.13 g (89%) of the desired product as an oil pureenough for use in the next step. FAB Mass Spec: 753.4 (M+Na).

EXAMPLE 30(2R)-2-[(2S)-2-(tert-Butyl-dimethylsilanyloxy)-3-tritylsulfanylpropyl]-nonanoicacid ((1S)-2,2-dimethyl-1-methylcarbonylpropyl)amide

Using the same procedure described in Example 29 6.80 g (11.26 mmol) ofthe product of Example 26 produced 7.71 g (94%) of the desired productas a colorless oil. FAB Mass Spec: 753.4 (M+Na).

EXAMPLE 31(2R,4R)-4-(tertButyldimethylsilanyloxy)-2-isobutyl-5-tritylsulfanylpentanoicacid ((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 29 5.81 g (10.33 mmol) ofthe product of Example 28 produced 4.62 g (65%) of the desired productas a colorless oil. ¹ H NMR (300 MHz, CDCl₃) δ 7.44 (m, 5H), 7.26 (m,10H), 6.16 (m, 1H), 5.96 (d, J=9 Hz, 1H), 4.19 (d, J=9 Hz, 1H), 3.58 (m,1H), 2.76 (d, J=4.7 Hz, 3H), 2.29 (dd, J=6.2,12 Hz 1H), 2.13 (dd,J=4.5,12 Hz, 1H), 2.0 (m, 1H), 1.7-1.1 (m, 3H), 0.92 (s, 9H), 0.85 (s,9H), 0.82 (dd, J=6,10 Hz), -0.039 (s, 3H), -0.078 (s, 3H).

EXAMPLE 32(2R,4S)-4-(tertButyldimethylsilanyloxy)-2-isobutyl-5-tritylsulfanylpentanoicacid ((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 29 7.20 g (12.81 mmol) ofthe product of Example 27 produced 5.53 g (63%) of the desired productas a colorless oil. Electrospray Mass Spec: 711.4 (M+Na)⁺.

EXAMPLE 33 (2R)-2-((2R)-2-Hydroxy-3-tritylsulfanylpropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

To a solution of 5.13 g (7.027 mmol) of the product of Example 29dissolved in 75 mL of THF was added 17.6 mL (0.01 8 mmol) of a 1.0Msolution of tetrabutylammonium fluoride in THF. The reaction mixture wasstirred at room temperature for 4 h and then diluted with ether. Theresulting solution was washed with water and brine, dried over MgSO₄,filtered and concentrated in vacuo. The residue was chromatographed onsilica gel eluting with EtOAc/Hexanes (gradient: 1:3-1:1) to provide2.78 g (64%) of the desired product as a colorless oil. ElectrosprayMass Spec: 617.5 (M+H)⁺.

EXAMPLE 34 (2R)-2-((2S)-2-Hydroxy-3-tritylsulfanylpropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 33 7.63 g (0.126 mmol) ofthe product of Example 30 produced 4.22 g (66%) of the desired productas a colorless oil. Electrospray Mass Spec: 617.5 (M+H)⁺.

EXAMPLE 35 (2R,4R)-4-Hydroxy-2-isobutyl-5-tritylsulfanylpentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 33 4.58 g (0.126 mmol) ofthe product of Example 31 produced 3.66 g (96%) of the desired productas a colorless oil. Electrospray Mass Spec: 575.4 (M+H)⁺.

EXAMPLE 36 (2R,4S)-4-Hydroxy-2-isobutyl-5-tritylsulfanylpentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 31 5.50 g (0.126 mmol) ofthe product of Example 30 produced 3.87 g (84%) of the desired productas a colorless oil. Electrospray Mass Spec: 575.3 (M+H)⁺.

EXAMPLE 37 (2R)-2-((2R)-2-Hydroxy-3-mercaptopropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

To a solution of 0.700 g (1.136 mmol) of the product of Example 33 and0.363 mL (2.273 mmol) of triethylsilane dissolved in 10 mL ofdichloromethane was dropwise added 10 mL of trifluoroacetic acid. Thereaction mixture was stirred at room temperature for 0.5 h and thenconcentrated in vacuo. The residue was chromatographed on silica geleluting with EtOAc/Hexanes (gradient: 1:3-1:1) to provide 0.263 g (62%)of the desired product as a colorless oil. Electrospray Mass Spec: 375.4(M+H)⁺.

EXAMPLE 38 (2R)-2-((2S)-2-Hydroxy-3-mercaptopropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 37 1.0 g (1.62 mmol) ofthe product of Example 34 produced 0.24 g (40%) of the desired productas a colorless oil. Electrospray Mass Spec: 375.4 (M+H)⁺.

EXAMPLE 39 (2R,4R)-4-Hydroxy-2-isobutyl-5-mercaptopentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 37 1.50 g (2.61 mmol) ofthe product of Example 35 produced 0.47 g (54%) of the desired productas a colorless oil. Electrospray Mass Spec: 333.3 (M+H)⁺.

EXAMPLE 40 (2R,4S)-4-Hydroxy-2-isobutyl-5-mercaptopentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 37 1.50 g (2.61 mmol) ofthe product of Example 36 produced 0.14 g (16%) of the desired productas a colorless oil. Electrospray Mass Spec: 333.3 (M+H)⁺.

EXAMPLE 41 (2R)-2-(2-oxo-3-tritylsulfanylpropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

To a solution of 0.962 g (1.562 mmol) of the product of Example 33 in 3mL of DMSO was added 0.505 mL (6.246 mmol) of pyridine followed by 0.120mL (1.562 mmol) of trifluoroacetic acid and 0.898 (4.685 mmol) of1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride. Thereaction mixture was stirred at room temperature for 36 h and thendiluted with 200 mL of EtOAc. The resulting solution was washed with 0.1N HCl solution, water, saturated NaHCO₃ solution and brine, dried overMgSO₄, filtered and concentrated in vacuo. The residue, 0.948 g (99%)was used in the next step without purification. Electrospray Mass Spec:615.4 (M+H)⁺.

EXAMPLE 42 (2R)-2-Isobutyl-4-oxo-5-tritylsulfanylpentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 41 1.25 g (2.18 mmol) ofthe product of Example 35 produced 1.25 g (100%) of the desired productas a colorless oil. Electrospray Mass Spec: 573.4 (M+H)⁺.

EXAMPLE 43 (2R)-2-(3-Mercapto-2-oxopropyl)nonanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 37 1.985 g (3.23 mmol) ofthe product of Example 41 produced 0.506 g (42%) of the desired productas a colorless oil. Electrospray Mass Spec: 373.4 (M+H)⁺.

EXAMPLE 44 (2R)-2-Isobutyl-5-mercapto-4-oxopentanoic acid((1S)-2,2-dimethyl-1-methylcarbamoylpropyl)amide

Using the same procedure described in Example 37 2.49 g (4.35 mmol) ofthe product of Example 42 produced 0.462 g (32%) of the desired productas a colorless oil. Electrospray Mass Spec: 331.3 (M+H)⁺.

Pharmacology

Table 1 summarizes the pharmacological data obtained for the fourdiastereomeric alcohols and two mercaptoketones of this invention whereR is isobutyl or heptyl. The pharmacological procedures follow thetable. The data show that the 2(S) hydroxy diastereomers have superiorand usexpected potency over the 2(R) hydroxy analogs both in vivo and invitro, the latter being less potent than the keto compounds.

                  TABLE 1                                                         ______________________________________                                        In vitro and In vivo Inhibition of Matrix Metalloproteinases                                         Colla- Stro-                                                genase  melysin Gela-                                                         IC.sub.50 IC.sub.50 tinase in vivo %                                       Ex-   (nM) or % (nM) or % IC.sub.50 Collagenase I                             ample R' R inhibition inhibition (nM) inhibition                            ______________________________________                                        43    ═O heptyl  30.0   28          0.73/50 mpk*                            44 ═O isobutyl 38.0 58% @  4.8/60 mpk                                         1 μM                                                                   38 2(S) heptyl 30.0 96% @  22.2/50 mpk                                         OH   0.1 μM                                                               40 2(S) isobutyl 41.0 51% @ 19 84.8/50 mpk                                     OH   1 μM                                                                 35 2(R) heptyl 72% @ 38% @  0.44/50 mpk                                        OH  1 μM 1 μM                                                          39 2(R) isobutyl 228 6% @ 106 20.4/50 mpk                                      OH   300 nM                                                                ______________________________________                                         *mpk = milligrams/kilogram                                               

Stromelysin Inhibition in vitro.

The assay is based on the cleavage of the thiopeptide substrate((Ac-Pro-Leu-Gly(2-mercapto-4-methylpen tanoyl)Leu-Gly-OEt), BachemBioscience) by the enzyme stromelysin, releasing the substrate productwhich forms a colorimetric reaction with DTNB((5,5'-dithiobis(2-nitrobenzoic acid)). The thiopeptide substrate ismade up as a 20 mM stock in 100% DMSO and stored frozen while the DTNBstock is dissolved in 100% DMSO and stored as a 100 mM stock at roomtemperature. Both the substrate and DTNB are diluted to ImM with assaybuffer (50 mM HEPES, pH 7.0, 5 mM CaCl₂) before use. The stock of humanrecombinant stromelysin (truncated, Affymax) is diluted with assaybuffer to a final concentration of 12.5 nM in the reaction.

The enzyme, DTNB, and substrate (10 μM final concentration) with/withoutinhibitor (total reaction volume of 200 μL) is added to a 96 well plateand then the increase in color is monitored spectrophotometrically for 5minutes at 405 nanometers (nm) on a plate reader. The increase in OD₄₀₅is plotted and the slope of the line is calculated which represents thereaction rate.

The linearity of the reaction rate is confirmed (r² >0.85). The mean ofthe control rate is calculated and compared for statistical significance(p<0.05) with drug-treated rates using Dunnett's multiple comparisontest. Dose-response relationships can be generated using multiple dosesof drug and IC₅₀ values with 95% CI are estimated using linearregression (IPRED, HTB) (Weingarten and Feder, Spectrophometric AssayFor Vertebrate Collagenase, Anal. Biochem 147, 437-440 (1985)).

Gelatinase Inhibition in vitro.

The assay is based on the cleavage of the thiopeptide substrate((Ac-Pro-Leu-Gly(2-mercapto-4-methylpentanoyl)Leu-Gly-OEt), BachemBioscience) by the enzyme gelatinase, releasing the substrate productwhich forms a calorimetric reaction with DTNB((5,5'-dithiobis(2-nitrobenzoic acid)). The thiopeptide substrate ismade up fresh as a 20 mM stock in 100% DMSO and the DTNB is dissolved in100% DMSO and stored in dark as a 100 mM stock at room temperature. Boththe substrate and DTNB are diluted to 1 mM with assay buffer (50 mMHEPES, pH 7.0, 5 mM CaCl₂, 0.2% Brij) before use. The stock of humanneutrophil gelatinase B is diluted with assay buffer to a finalconcentration of 0.15 nM.

The assay buffer, enzyme, DTNB, and substrate (500 μM finalconcentration) with/without inhibitor (total reaction volume of 200 μL)is added to a 96 well plate and then the increase in color is monitoredspectrophotometrically for 5 minutes at 405 nanometers (nm) on a platereader. The increase in OD₄₀₅ is plotted and the slope of the line iscalculated which represents the reaction rate.

The linearity of the reaction rate is confirmed (r² >0.85). The mean ofthe control rate is calculated and compared for statistical significance(p<0.05) with drug-treated rates using Dunnett's multiple comparisontest. Dose-response relationships can be generated using multiple dosesof drug and IC₅₀ values with 95% CI are estimated using linearregression (IPRED, HTB). (Weingarten and Feder, Spectrophometric AssayFor Vertebrate Collagenase, Anal. Biochem 147, 437-440 (1985)).

Collagenase Inhibition in vitro

The assay is based on the cleavage of a peptide substrate((Dnp-Pro-Cha-Gly-Cys(Me)-His-Ala-Lys(NMa)-NH₂), Peptide International,Inc.) by collagenase releasing the fluorescent NMa group which isquantitated on the fluorometer. Dnp quenches the NMa fluorescence in theintact substrate. The assay is run in HCBC assay buffer (50 mM HEPES, pH7.0, 5mM Ca⁺², 0.02% Brij, 0.5% cysteine), with human recombinantfibroblast collagenase (truncated, mw 18,828, WAR, Radnor). Substrate isdissolved in methanol and stored frozen in 1 mM aliquots. Collagenase isstored frozen in buffer in 25 μM aliquots. For the assay, substrate isdissolved in HCBC buffer to a final concentration of 10 μM andcollagenase to a final concentration of 5 nM. Compounds are dissolved inmethanol, DMSO, or HCBC. The methanol and DMSO are diluted in HCBC to<1%. Compounds are added to the 96 well plate containing enzyme and thereaction is started by the addition of substrate.

The reaction is read (excitation 340 nm, emission 444 nm) for 10 minutesand the increase in fluorescence over time is plotted as a linear line.The slope of the line is calculated and represents the reaction rate.

The linearity of the reaction rate is confirmed (r² >0.85). The mean ofthe control rate is calculated and compared for statistical significance(p<0.05) with drug-treated rates using Dunnett's multiple comparisontest. Dose-response relationships can be generated using multiple dosesof drug and IC₅₀ values with 95% CI are estimated using linearregression (IPRED, HTB) (Bickett, D. M. et al., A High ThroughputFluorogenic Substrate For Interstitial Collagenase (MMP-1) andGelatinase (MMP-9), Anal. Biochem. 212, 58-64 (1993)).

In vivo MMP Inhibition

A 2 cm piece of dialysis tubing (molecular weight cut-off 12-14,000, 10mm flat width) containing matrix metalloproteinase enzyme (stromelysin,collagenase or gelatinase in 0.5 mL of buffer) is implanted either ip orsc (in the back) of a rat (Sprague-Dawley, 150-200 g) or mouse (CD-1,25-50 g) under anesthesia. Drugs are administered PO, IP, SC or IVthrough a cannula in the jugular vein. Drugs are administered in a dosevolume of 0.1 to 0.25 mL/animal. Contents of the dialysis tubing iscollected and enzyme activity assayed.

Enzyme reaction rates for each dialysis tube are calculated. Tubes fromat least 3 different animals are used to calculate the mean±sem.Statistical significance (p<0.05) of vehicle-treated animals versusdrug-treated animals is determined by analysis of variance. (Agents andActions 21: 331, 1987)

Pharmaceutical Composition

Compounds of this invention may be administered neat or with apharmaceutical carrier to a patient in need thereof. The pharmaceuticalcarrier may be solid or liquid.

Applicable solid carriers can include one or more substances which mayalso act as flavoring agents, lubricants, solubilizers, suspendingagents, fillers, glidants, compression aids, binders ortablet-disintegrating agents or an encapsulating material. In powders,the carrier is a finely divided solid which is in admixture with thefinely divided active ingredient. In tablets, the active ingredient ismixed with a carrier having the necessary compression properties nsuitable proportions and compacted in the shape and size desired. Thepowders and tablets preferably contain up to 99% of the activeingredient. Suitable solid carriers include, for example, calciumphosphate, magnesium stearate, talc, sugars, lactose, dextrin, starch,gelatin, cellulose, methyl cellulose, sodium carboxymethyl cellulose,polyvinylpyrrolidine, low melting waxes and ion exchange resins.

Liquid carriers may be used in preparing solutions, suspensions,emulsions, syrups and elixirs. The active ingredient of this inventioncan be dissolved or suspended in a pharmaceutically acceptable liquidcarrier such as water, an organic solvent, a mixture of both orpharmaceutically acceptable oils or fat. The liquid carrier can containother suitable pharmaceutical additives such a solubilizers,emulsifiers, buffers, preservatives, sweeteners, flavoring agents,suspending agents, thickening agents, colors, viscosity regulators,stabilizers or osmo-regulators. Suitable examples of liquid carriers fororal and parenteral administration include water (particularlycontaining additives as above, e.g., cellulose derivatives, preferablesodium carboxymethyl cellulose solution), alcohols (including monohydricalcohols and polyhydric alcohols, e.g., glycols) and their derivatives,and oils (e.g., fractionated coconut oil and arachis oil). Forparenteral administration the carrier can also be an oily ester such asethyl oleate and isopropyl myristate. Sterile liquid carriers are usedin sterile liquid form compositions for parenteral administration.

Liquid pharmaceutical compositions which are sterile solutions orsuspensions can be utilized by, for example, intramuscular,intraperitoneal or subcutaneous injection. Sterile solutions can also beadministered intravenously. Oral administration may be either liquid orsolid composition form.

The dosage to be used in inhibiting the matrix metalloproteinases in apatient must be subjectively determined by the attending physician. Thevariables involved include the severity of the dysfunction, and thesize, age, and response pattern of the patient. Treatment will generallybe initiated with small dosages less than the optimum dose of thecompound. Thereafter the dosage is increased until the optimum effectunder the circumstances is reached. Precise dosages will be determinedby the administering physician based on experience with the individualsubject treated and standard medical principles.

Preferably the pharmaceutical composition is in unit dosage form, e.g.,as tablets or capsules. In such form, the composition is sub-divided inunit dose containing appropriate quantities of the active ingredient;the unit dosage form can be packaged compositions, for example packedpowders, vials, ampoules, prefilled syringes or sachets containingliquids. The unit dosage form can be, for example, a capsule or tabletitself, or it can be the appropriate number of any such compositions inpackage form.

What is claimed is:
 1. A process for the preparation of a compoundaccording to the formula ##STR9## where R¹ is C₁ -C₁₂ alkyl, straight orbranched and optionally substituted by halogen, hydroxy, C₁ -C₆ alkoxy,amino, carboxyl, C₁ -C₆ alkoxycarbonyl, carboxamido, nitrile, mono- ordi-(C₁ -C₆)alkylamino, thio, C₁ -C₆ alkylthio, aryl, --Oaryl or --OCH₂aryl where aryl is optionally substituted with C₁ -C₆ alkyl, C₁ -C₆alkoxy, carboxy, halogen, cyano, nitro, carboxamido, or hydroxy; and C₁-C₆ alkanesulfonyloxy and aryl is a 5 to 10 membered carbocyclic orheterocyclic mono or bicyclic aromatic group selected from the benzene,furan, thiophene, imidazole, naphthalene, quinoline, indole,benzothiophene, benzimidazole, pyridine, pyrimidine, and benzofuran; andR² and R⁶ together form carbonyl which comprises:(1) oxidation ofcompound of the formula ##STR10## or ##STR11## where R¹, R² and R⁶ areas previously defined, Y is hydrogen and Z is phenyl, --CR³ R⁴ R⁵ whereR³, R⁴ and R⁵ are independently H, methyl, --O--C₁ -C₁₂ alkyl,O-tetrahydropyranyl, --S-benzyl, phenyl optionally substituted withmethoxy, hydroxy, nitro, or methyl; disulfides or any other groupsuitable for protecting sulfur, and (2) removal of the thiol protectinggroup to give a compound where R² and R⁶ together forms carbonyl.
 2. Theprocess according to claim 1 for the preparation of a compound accordingto the formula ##STR12## where R¹ is C₁ -C₁₂ alkyl, straight or branchedand optionally substituted by halogen, hydroxy, C₁ -C₆ alkoxy, amino,carboxyl, C₁ -C₆ alkoxycarbonyl, carboxamido, nitrile, mono- or di-(C₁-C₆)alkylamino, thio, C₁ -C₆ alkylthio, aryl, --Oaryl or --OCH₂ arylwhere aryl is optionally substituted with C₁ -C₆ alkyl, C₁ -C₆ alkoxy,carboxy, halogen, cyano, nitro, carboxamido, or hydroxy; and C₁ -C₆alkanesulfonyloxy and aryl is a 5 to 10 membered carbocyclic orheterocyclic mono or bicyclic aromatic group selected from the benzene,furan, thiophene, imidazole, naphthalene, quinoline, indole,benzothiophene, benzimidazole, pyridine, pyrimidine, and benzofuran; andR² and R⁶ together form carbonyl which comprises:(1) oxidation ofcompound of the formula ##STR13## or ##STR14## where R¹, R² and R⁶ areas previously defined, Y is hydrogen and Z triphenylmethyl,withdimethylsulfoxide/pyridine/trifluoroaceticacid/1-(3-dimethylaminopropyl)-3-ethylcarbodiimide or equivalentactivated dimethylsulfoxide oxidation or other oxidative methodsincluding Dess-Martin reagent, pyridinium dichromate, pyridiniumchlorochromate/sodium acetate, tetrapropylammonium perruthenate/NMO and(2) removal of the triphenylmethyl thiol protecting group to give acompound where R² and R⁶ together forms carbonyl and Z is H.